* {
  margin: 0;
  padding: 0;
}
body {
  background: #eee;
}
button {
  width: 60px;
  height: 25px;
  margin-left: 10px;
  background: gold;
  border: none;
  outline: none;
  border-radius: 5px;
}
.show button {
  background: red !important;
  color: #fff;
}
h3 {
  margin: 10px;
  position: sticky;
  top: 55px;
  background: #eee;
}
